Tutorial

Darken a sky and brighten the subject with AI masks

Updated 15 October 2026 · about 10 minutes

A bright sky and a dark subject is the classic RAW problem: expose for one and the other suffers. In this tutorial you'll use two masks Raw Smith finds for you, Sky and Subject, to bring the sky down and the subject up separately. Then you'll refine them with subtract and intersect, check them with the overlay, and blend the result with Amount.

What you need

A photo with a sky and a clear subject: a person, an animal or a building against the sky works well.
Its global edits roughly done. Masks work on top of the Edit panels, so set the overall light first (the first tutorial covers that).

Step 1: Open the Masks tab

Open the photo in the editor and choose Masks (⇧W or M on a keyboard).

The panel lists the photo's masks; with none yet it says Pick what to select. Each mask has its own light and color edits. Tap New Mask to see the tiles. The ones Raw Smith finds in the photo (Subject, Sky, Background, People, Face, Object) show Looking for subjects… for a moment while it analyses the photo on your device, and None found in this photo if there isn't one.

Step 2: Add a Sky mask

Tap the Sky tile to create a mask that covers just the sky.

The mask opens straight away. Press O, or tap Overlay, to see its coverage in red, and check that the edges follow the horizon, trees and rooftops. With Apple ProRAW, the mask uses the sky matte your iPhone saved in the file.

Step 3: Darken the sky

In the mask's Light controls, lower Highlights and then Exposure until the clouds have shape again.

Start with Highlights, which brings back the brightest clouds without dulling the whole sky, then lower Exposure a little. Switch to the mask's Color controls for Temperature (a little cooler gives a deeper blue) and Saturation, and to Effects for Dehaze on a hazy day. Turn the overlay off with O to judge the result.

Step 4: Add a Subject mask

Go back to the mask list, tap New Mask and choose Subject.

Raw Smith picks the photo's main subject. For a person, People lets you choose everyone or one person, and Face just a face. Object selects whatever you tap in the photo. Each mask keeps its own edits, so the sky's changes stay as they are.

Step 5: Brighten the subject

Raise the Subject mask's Exposure and Shadows, then add a little Clarity under Effects.

Small moves look most natural: a third of a stop of Exposure is often enough. Clarity adds mid-tone contrast that makes the subject stand out; Texture brings out fine detail such as fabric or fur. For a portrait, go easy with both on skin.

Step 6: Refine the mask with subtract or intersect

If a mask covers too much, use − to subtract another part from it, or ∩ to keep only what two parts both cover.

For example, if the Subject mask includes a lamp post you don't want brightened, choose − and then Brush, and paint over the post: it leaves the mask. To lighten only the bottom of the subject, choose ∩ and then Linear, and drag the gradient up from the bottom. + adds more coverage the same way. With a brush you can set Size, Feather and Flow, and switch between Paint and Erase. On iPad, Apple Pencil paints with pressure, and double-tapping the Pencil switches between Paint and Erase.

Step 7: Blend with Amount and check before and after

Use each mask's Amount slider to dial its effect up or down, then press and hold the photo to compare with the original.

Amount scales all of a mask's edits together, which is the quickest way to tone down a sky that went too dark. The eye button in the mask list hides a mask's edits so you can judge them on and off, and the ⋯ menu has Rename…, Duplicate, Invert and Delete. Renaming helps once a photo has several masks.

Where to go next

Masks in detail: brushes, gradients, colour and luminance ranges, and every per-mask control.
Save a preset that includes subject, sky and people masks, to reuse on similar photos.
Remove dust and distractions with Heal and Clone.
The Edit panels and keyboard shortcuts.

Questions

Are Raw Smith's AI masks made on my device?

Yes. Subject, Sky, Background, People, Face and Object masks are found on your iPhone, iPad or Mac with Apple's Vision framework. The photo isn't uploaded anywhere.

How do I see what a mask covers?

Press O, or turn on Overlay in the open mask. What the mask covers shows in red on the photo.

Can I remove part of an AI mask?

Yes. Use − (subtract) in the open mask and add another part, such as a brush or a gradient, to take away from it, or ∩ (intersect) to keep only where two parts overlap.

Does ProRAW give better sky masks?

With Apple ProRAW, the Sky mask uses the sky matte the iPhone saved in the file.